Treated tobacco composition



Jan. 20, 1970 J. F. MARTIN 3,490,462

TREATED TOBACCO COMPOSITION Filed Feb. 1, 1967 2 Sheets-Sheet 1 INVENTOR.

JOSEPH F. MARTIN BY ATTORNEYS Jan. 20, 1970 J. F. MARTIN 3,490,462

TREATED TOBACCO COMPOSITION Filed Feb. 1, 1967 2 Sheets-Sheet 2 BOILING POINT AT 760 MM ICAL N' PA A FINS TEMPERATURE AT WHICH COMPOUND DEVELOPS IMM. VAPOR PRESSURE MELTING POINT ROOM TEMPERATURE CARS NATOMS QUID EGLIGIBLE VAPOR PRESSURE LING POINT MB ROF can 4 e e no l2 I4 l6 I8 20 22 24 2e 29 INVENTOR. 5 JOSEPH F MARTIN Tao/w, TWJM ATTORNEYS United States Patent 3,490,462 TREATED TOBACCO COMPOSITION Joseph F. Martin, Painesville, Ohio, assignor, by direct and mesne assignments, of one-fourth to Marmanac, Inc., Cleveland, Ohio, a corporation of Ohio, and onehalf to Chemfilt Corp. of America, North Tarrytown, N.Y., a corporation of New York Filed Feb. 1, 1967, Ser. No. 613,351 Int. Cl. A24b 15/06 US. Cl. 13117 Claims ABSTRACT OF THE DISCLOSURE Tobacco compositions are disclosed which include as additives saturated hydrocarbon parafiins, particularly the normal parafiins, useful in reducing the benzo- (a) pyrene contents of the smoke and in producing a smooth, mild taste therefor. The effective paraffins have the general formula C H are liquid at ambient temperature and at least one includes 11 to 18 carbon atoms in the chain.

BACKGROUND OF THE INVENTION The present invention relates to the treatment of gaseous media, and more particularly relates to smoking mixtures and/ or materials such as tobacco; and to smoking articles such as cigarettes or cigars for reducing the benzo (a) pyrene from the gaseous media and to provide a smooth, mild taste thereof.

Previous studies, including the Report of the Advisory Committee to the Surgeon General of the Public Health ServicePublication No. 1103have discussed the harmful effects of smoking, particularly in relation to cigarettes. Such studies have established that certain chemical compounds are cancer-producing (carcinogenic). Most of the carcinogenic compounds identified in cigarette smoke tar are not present in the native tobacco leaf, but are formed by pyrolysis at the high burning temperature of the cigarette material. At least seven polycylic hydrocarbons which are also carcinogens have been identified in tobacco smoke. Examples of strongly carcinogenic compounds of this type include benzo (a) pyrene, dibenzo (a, i) pyrene and dibenzo (a, h) anthracene. Benzo (a) pyrene is by far one of the most potent of the strongly noted carcinogens detected in tobacco smoke and is present in a much larger quantity as compared to any of the other carcinogenic compounds.

The species Nicotina tabacumis now the chief source of smoking tobacco cultivated in the United States. The present invention, however, relates to any type of tobacco. The tobacco leaf contains a complex mixture of chemical substances, such as cellulosic products, starches, proteins, hydrocarbons, etc. The smoke of a cigarette is a heterogeneous mixture of gases, uncondensed vapors and liquid particulate matter. As the smoke enters the mouth it is a concentrated aerosol with millions or billions of particles per cubic centimeter. The size of the particles of the aerosol range is from less than 0.1 micron to about 5 microns; and are counted in the billions per cubic centimeter of smoke. When tobacco is smoked, and the smoke condensed or otherwise collected, the condensate, known as tobacco tars, contains the particulate phase of the smoke, and most of the easily condensable components of the gas phase. The reported amount of -tar, from the smoke of one cigarette is between about three and 40 mg., the quantity varying according to the burning and condensing conditions, the length of the cigarette, the use of a filter, porosity of paper, content of tobacco, weight and kind of tobacco employed. While 3,490,462 Patented Jan. 20, 1970 air is being drawn through the cigarette the temperature of the burning zone reaches approximately 884 C. and when the cigarette is burning without air being drawn through it the temperature is approximately 835 C. At the temperatures cited, extensive pyrolytic reactions occur in the tobacco to produce the aforementioned carcinogenic effects in the tobacco smoke.

Examples of the types of pyrolysis which contribute to the contamination of air with carcinogens include industrial processes such as the destructive distillation of coal and wood, smoking of food products such as meats, burning of fuel in a diesel or gasoline engine, incineration of trash, and probably most important from the aspect of lung cancer, the pyrolysis of tobacco during smoking.

While the present invention has applicability to the treatment of any gas stream containing carcinogenic hydrocarbons, it will be described most particularly with respect to tobacco smoke.

It has been found that generally one cigarette will produce about 20 to 30 mg. of tars while one thousand cigarettes will produce about 38 micrograms of benzo (a) pyrene. It has further been determined that benzo (a) pyrene constitutes about percent of all of the presently known cancer-producing ingredients in the tars and has a potency of about ten thousand as compared to most of the other carcinogens in the tars. Moreover, if the benzo (a) pyrene content of the smoke can be substantially reduced, then possibly the total carcinogenic property of the smoke can also be effectively reduced.

In accordance with the present invention, there is provided a control for the aforementioned carcinogenic substances which contemplates incorporating with the smoking mixtures and/or materials, a liquid N-paraffin in an amount sufficient to reduce the carcinogenic content of the smoke, and to improve the taste thereof.

The foregoing objects, as Well as others, will become apparent from the following description in conjunction with the accompanying drawings, wherein:

FIG. 1 is a perspective view partially in section showing a cigarette made in accordance with the invention;

FIG. 2 is a perspective view partially in section show ing a filter for use with a cigarette or the like made in accordance with the invention;

FIG. 3 is a perspective view partially in section showing the filter as in FIG. 2 made integral with a cigarette as in FIG. 1; I

FIG. 4 is a perspective view partially in section showing a holder for cigarettes, cigars or the like made in accordance with the invention; and

FIG. 5 is a graphic illustration showing certain of the physical and chemical properties of the selective range of the N-paraflins used in accordance with the invention.

SUMMARY OF THE INVENTION In general, the foregoing objects and other related advantages are achieved in accordance with the present invention by treating a smoking mixture in one form, such as tobacco, with a control substance in the class of saturated hydrocarbon paraflins. Preferably, a liquid, straight or continuous chain hydrocarbon, such as the normal (N) paraifins, are used in an amount sufficient to substantially reduce the benzo (a) pyrene content of the smoke. When treating a smoking mixture, such as tobacco, the N-paraflin is present in the range from about 0.1% to 3%, based on the weight of the tobacco. Below 0.1% the effect is somewhat diminished, and above 2.5% the tobacco becomes oily in nature. Preferably, the range is from about 0.1% to 1.6%, based on the weight of the tobacco.

3 DESCRIPTION OF PREFERRED EMBODIMENTS- The practice of the invention may be illustrated by the following examples without, however, being considered as limited thereto.

Example A A mixture of heavy fraction N-parafiins, such as dodecane about 13%, tridecane about 49.7%, tetradecane about 37%, pentadecane etc. about 2%, was subjected to distillation until the boiling point of the material in the still rose to about 218 C. About 3% of the original weight was removed. The material left in the still was virtually odorless. Then 3.6 grams of the mixture was mixed with 10 grams of water and a trace of dispersing agents Igepal CO430 and CO-850. In each case, the amount used was less than .005 gram. The mixture was shaken and a white emulsion resulted which remained stable for 30 minutes.

Example I One pound of shredded tobacco, identical to that used in making commercial cigarettes, was sprayed with 13.6 grams of the N-paraffin-water emulsion described in Example A above. The tobacco was then mixed, by tumbling, in a gas tight tumbler for 30 minutes. The tobacco was then made into cigarettes on a small commercial machine, using approximately one (1) gram of tobacco per cigarette. The cigarettes were 68 mm. long. Several hundred such cigarettes, and several hundred made in an identical manner, but without treating the tobacco, were aged for 72 hours at 70 F. and 60% relative humidity, then smoked in a smoking machine built by Byrd & Phipps of Richmond, Va.

The cigarettes were all smoked to butt length of 18 mm. and the tars collected on Cambridge filters, using one (1) filter per eight (8) cigarettes. The smoking cycle was 30 seconds, with two (2) seconds draw and two (2) seconds discharge. The volume drawn at each puff was 35 ml. Each cigarette yielded from 9-10 puffs.

The tars were analyzed for benzo (a) pyrene with the Davis, Lee & Davison method. The untreated cigarettes yielded tars containing 28 micrograms of benzo (a) pyrene per 1000 cigarettes, while the treated cigarettes yielded only micrograms per 1000 cigarettes, or a reduction of 82% in benzo (a) pyrene.

Example II Example I above was repeated, except that the light fraction of the N-paraffins, such as decane about 12.8% undecane about 40.9%, dodecane about 37.5%, tridecane 8.5%, tetradecane etc. about 2%, was used. The light fractions were first subjected to distillation to attain a boiling point'of 205 C. by this distillation, most of the decane and all of the odorous branched chain compounds were removed. In this case, the treated cigarettes, carrying 3.6 grams of N-paraflins per one (1) pound of tobacco, or 0.8%, based on the tobacco weight, yielded only 2 micrograms of benzo (a) pyrene per 1000 cigarettes giving a reduction of more than 93% in benzo (a) pyrene.

After separation of the benzo (a) pyrene in accordance with the method of H. J. Davis, L. A. Lee and T. R. Davidson of Summit Research Laboratories, Celanese Corporation of America, the instrument used to evaluate the benzo (a) pyrene was a Ferrand Spectro fluorirneter. Because this instrument can detect and evaluate a concentration of 0.01 microgram per ml. of benzo (a) pyrene, it is believed that the method of treatment in accordance with Example H produced a substantially complete elimination of benzo (a) pyrene.

In accordance with the invention, the N-paraflins are present or applied in the range from 0.1% to 3%, based on the weight of the tobacco. Preferred results are achieved with a range from about 0.1% to 1.6%, based on the weight of the tobacco. Similarly, for treating filter material the range is about 1.0% to 12%, based on the weight'of the filter material. Preferred-results achieved with about 4%, based on the weight of the filter material.

Suitable flavoring ingredients, humectants, and the like may be admixed with the tobacco and/or with the N- parafiins. For example, the humectant may be present in the amount of 3% and moisture present in the amount of 12% to 12 /2% based on the weight of the tobacco, when dry. The humectant may be any suitable material, such as glycerin or other polyhydric alcohol, as known in the art. The tobacco to which the N-paraffins are applied may be in a form suitable for direct use in a cigarette or other smoking article for which it is to be applied. For example, a tobacco which has been aged, humected, shredded and treated with other tobacco-treating ingredient may be used, as desired.

Because of the physical problems of thoroughly mixing, such as 0.8% of the N-paraffins with tobacco, it is preferred that the N-paraflins be diluted with a diluent. However, prolonged mixing will achieve a homogeneous mixture. This diluent can be Water, however, the N- paraffins and water do not easily mix, but the paraffins can easily be emulsified in the water by means well known in the art. Diluents or dispersing agents which may be employed include soapsthe sodium, potassium or ammonium salts of acids, sulphonates, ethylenated alcohols, oxonium compounds, and many others which in one way or another reduce surface tension and cause dispersion. It is preferred that ammonium soaps or ethylenated alcohols be used. The former may include ammonium palmitate and the latter may include Igepal CO-430 and 850. The dispersing agent may be mixed either with the N-paraffins or with the water.

The quantity of the dispersing agent may be from about 0.1% to 0.01%, based on the weight of the N-parafiins. Preferably, the amount is just sufficient to produce a temporary emulsion. It is to be noted, however, that the diluent may be a volatile and harmless hydrocarbon, such as hexane, or any reasonably volatile and non-toxic organic solvent, such as the alcohols, esters, etc. Moreover, the diluent takes no part in the reaction, but is a transient material employed to distribute the N-parafiin on the tobacco and/ or filter material.

The preferred control substance for reducing the carcinogenic effects of the tobacco smoke or smoking articles in accordance with the invention are the normal or N-parafiins (straight chain) which can be defined by the general formula C H The hydrocarbon molecules, or the straight chain paraffin materials may be made of carbon chains having carbon atoms in the range from 11 to 20. Preferably, the range is from 11 to 18 carbon atoms. In this preferred range, the vapor pressure would be very low at ambient temperature. For example, it has been determined that an N-paraffin with 11 carbon atoms produces a vapor pressure of one (1) mm. at ambient temperature. Moreover, other such hydrocarbons having a carbon content higher than 11, such as 12, 13, 14, etc., all produce less vapor pressure at room temperature. Prefer-ably, the vapor pressure of the material is one 1) mm. or below. It has also been found that the melting point of the preferred range is such that the hydrocarbon is liquid at ambient temperature Preferably, the melting point is in the range from minus 26.5 C. to 28 C. The boiling point for the preferred range may be between about 195.8 C. to 317 C. at 760' mm. pressure. Preferably, the boiling point is above 200 C. Reference may be had to FIG. 5 which graphically shows the melting points, boiling points and temperatures at which the N-parafiins develop one (1) of vapor pressure. It has been found that hydrocarbons of this type having in excess of 18 carbon atoms tend to become wax-like at ambient temperature. It has been found, however, that such hydrocarbons may be employed having in excess of 18 carbon atoms when mixed with normal parafiins having carbon atoms in the preferred range from 11 t 18 so that the mixture is in the form of a liquid at ambient temperature. It is believed that due to the low vapor pressure of the normal parafiins they have little, if any, odor. Examples of such N-paraflins which may be employed include undecane, dodecane, etc., up to triacontane. In the preferred range, the N-paraflins include undecane up to and including octadecane.

When the N-paraflins are distilled either in air or in steam, most of the odorous branched chain compounds are removed. The residual mixtures of N-parafiins have extremely faint and slightly pleasant odors. The specific mixture of N-paraffins is dependent upon the source of the crude petroleum and the methods used to isolate the N-paraflins. Any mixture of N-parafiins containing undecane to octadecane may be used so long as the mixture thereof is liquid at room temperature. Beyond octadecane, the N-parafiins are waxes at ambient temperature. They are useful in the present invention provided they are soluble in the other, lower melting point N-parafiins, at ambient temperature. Thus other mixtures containing compounds as large as hexacontane C H may be used provided the total composition remains liquid at ambient temperatures. Compounds below undecane exhibit vapor pressures at ambient temperatures which would cause them to evaporate slowly and so disappear from sight (i.e., from the tobacco, or filter material) after a short period of time. For example, undecane has such a low vapor pressure at ambient temperatures (70 F.35 C.), that it would be expected to remain on the tobacco, or filter material for a very long period of time, such as one (1) year or more.

In addition to cigarettes, it is contemplated adding the disclosed normal paraifins to cigarette filters and cigarette holders. In FIG. 1 there is shown a cigarette 2 which comprises a wrapper 4 of cigarette paper. Inside the wrapper 4 is disposed a quantity of tobacco 6 treated with N-parafins in accordance with the invention. In FIG. 2 there is shown a filter 8 for a cigarette which can be composed of any absorbent material 10. The absorbent material 10 may be a fibrous and/or granular material, such as cellulose acetate, cotton, porous paper, charcoal, clay, silica or the like as known in the art and treated with the N-parafiins as disclosed. Accordingly, the filter 8 may be made as an integral part of the cigarette of FIG. 1 by being integral with the column of tobacco as seen in FIG. 3, or maybe made separate therefrom as seen in FIG. 2. It is to be noted, however, that the filter 8 could also be used in smoking pipes and in cigarette or cigar holders 12 of the type shown in FIG. 4 either as in integral or removable component thereof. As shown, the holder could have a flared end, as at 14, to accommodate variations in cigarette or filter tip cigarette dimensions. It is to be noted that many variations of this type of holder may be employed, such as larger ones for cigars, highly decorated types, and others with very long filter sections.

From the foregoing description and accompanying drawings, it will be seen that in accordance with the present invention that smoking tobacco or smoking articles treated in accordance with the invention exhibit substantially reduced carcinogen content as compared to commercial non-treated cigarettes and that such tobacco and/ or smoking articles have an improved smooth, pleasant taste.

I claim:

1. A tobacco smoking mixture for reducing the benzoalpha-pyrene content of the smoke from said mixture upon pyrolysis thereof comprising, a major portion of a tobacco composition material, and a minor portion of a normal paraffin substance having the general formula C H and present in the amount from approximately 0.1% to approximately 3.0% based on the weight of said tobacco composition material, said normal paraffin substance being liquid at ambient temperature and being distributed in wetting relation throughout said tobacco composition material, said normal paraflin substance including at least one normal paraffin having from 11 to 18 carbon atoms in the molecular chain thereof, whereby upon pyrolysis of said mixture said normal parafiin substance acts with said smoke to reduce the hemealpha-pyrene content thereof.

2. A tobacco smoking mixture in accordance with claim 1, wherein said normal parafiin has a vapor pressure of not greater than one millimeter at ambient temperature.

3. A tobacco smoking mixture in accordance with claim 1, wherein said normal paraifin substance includes at least one other normal parafiin having more than 18 carbon atoms in the molecular chain thereof, and said other normal paraifins being soluble in said first mentioned normal paraffin at ambient temperature.

4. A tobacco making mixture in accordance with claim 1, wherein said normal parafiin is a liquid emulsion including water and a dispersing agent.

5. A tobacco smoking mixture in accordance with claim 1, wherein said normal parafiin has a melting point from minus 26 C. to plus 28 C. with a boiling point from 198 C. to 317 C. at 760 mm. pressure.

References Cited UNITED STATES PATENTS 2,158,565 5/1939 Andrews 131-17 2,904,050 9/1959 Kiefer et a1. 131267 X 3,033,212 5/1962 Touey et al. 131-267 OTHER REFERENCES The Chemistry and Technology of Tobacco (Text) A. A. Shmuk pub. by Pischepromizdat, Moscow, 1953, translated by National Science Foundation, Available Office of Technical Services, US. Dept. of Commerce, Wash. DC P.st Cat. No. 96, pp. 500 & 501 cited.

Smoking and Health, Report of the Advisory Committee to the Surgeon General, publication (1964) Public Health Service Publication No. 1103, p. 51 cited.

MELVIN D. REIN, Primary Examiner US. Cl. X.R. 131l40, 200, 267 

